Self-Assembled Copper–Amino Acid Nanoparticles for in Situ Glutathione “AND” H2O2 Sequentially Triggered Chemodynamic Therapy

Two-step upconversion-driven PDT/CDT cooperative phototherapeutic platform based on surface magnetic field modulation

Photodynamic therapy utilizes photosensitizer to generate reactive oxygen species (ROS) under irradiation of light for anticancer. However, due to the strong absorption of visible light by tissues and organs, photodynamic therapy meets challenges in deep tissues. Herein, we propose an upconversion-driven photodynamic therapy combined with chemodynamic therapy based on UCNP@SiO2@Fe3O4@MC540. Upon the excitation of 980 nm laser, the visible emission of upconversion nanoparticles activates MC540 to produce ROS, which is enhanced by Fe3O4 through magnetic field modulation. Subsequently, Fe3O4 degrades under acidic conditions to produce ·OH via Fenton-reaction for chemodynamic therapy. The in vitro and in vivo experiments indicate that the two-step cooperative strategy exhibits significant anticancer efficacy. Besides, Finite Difference Time Domain (FDTD) simulation reveals that the enhancement stems from surface electric field and light absorption. It offers a deeper understanding of phototherapeutic process.

Acidity-unlocked glucose oxidase as drug vector to boost intratumor copper homeostatic imbalance-enhanced cuproptosis for metastasis inhibition and anti-tumor immunity

As one of the key tools of biocatalysis, natural enzymes have received extensive attention due to their unique activity. However, the non-selective catalysis and early leakage induced by delivery dependency of natural enzymes can cause side effects on normal tissues. Moreover, although cuproptosis is an emerging tumor-inhibiting programmed cell death, the occurrence of cuproptosis leads to high expression of Cu-dependent lysyl oxidase-like 2 (LOXL2), which promotes tumor metastasis. Herein, in order to intelligently regulate the "OFF-to-ON" catalytic activity of glucose oxidase (a natural enzyme called GOx) and simultaneously inhibit tumor metastasis caused by Cu imbalance, an acidity-unlocked GOx system drug carrier was constructed by co-assembling Cu ions and omeprazole (OPZ) on GOx exposing sulfhydryl and hydrophobic pockets. The GOx activity is significantly inhibited due to the coordination of Cu ions with sulfhydryl groups and the interaction of hydrophobic small molecule OPZ with hydrophobic bags, which results in specificity for tumor cells and ensures the safety of GOx in blood circulation. Meanwhile, dysregulation of intracellular Cu homeostasis that impairs the Cu-dependence of LOXL2 not only inhibits critical signaling during epithelial-mesenchymal transformation (EMT) and extracellular matrix (ECM) remodelling to prevent tumor metastasis, but also exacerbates enhanced cuproptosis induced by tumor metabolic stress, thereby reversing the immunosuppressive microenvironment. This strategy of acidity-unlocked the catalytic function of natural enzymes and LOXL2 activity inhibition provides a novel option for enhancing cuproptosis to inhibit tumor metastasis and anti-tumor immunity.

H2O2/O2 Self-Supplied Nanoplateform for amplifying oxidative stress to Accelerate Photodynamic/Chemodynamic therapy Cycles

Photodynamic (PDT) and chemodynamic therapies (CDT) relying on reactive oxygen species-mediated treatments mainly face various challenges of hypoxia, endogenous hydrogen peroxide (H2O2) deficiency, and glutathione (GSH) overexpression in the tumor microenvironment. Herein, we propose a novel strategy using a core-shell structured nanocomposite, UCNP@mSiO2@5-ALA-CaO2-Cu(UA@CC). The strategy centers on upconverting NPs and then utilizes mesoporous silica loaded with 5-aminolevulinic acid (5-ALA) to maximize the enrichment of protoporphyrin IX (Pph IX), an intra-tumor photosensitizer. Then in the acidic tumor microenvironment (TME), CaO2 in the outer layer reacts with H2O to form O2, H2O2 and Ca2+, and the released H2O2 serves as an auxiliary "fuel" to induce acceleration of the Fenton-like (Cu2+) reaction and inactivation of the antioxidant GSH enzyme, thus enhancing the tumor cells' Catalysis. Furthermore, under the excitation of a 980 nm laser, 5-ALA-mediated PDT and Cu+-based CDT were initiated. Through interconnected processes of Ca2+ overload, self-supply of H2O2/O2, and enhanced GSH depletion, an accelerated cycling strategy for combined PDT/CDT therapy was established, resulting in amplified oxidative stress and anti-tumor capabilities, which was validated in cancer cells and melanoma mouse models.

Copper-coordination driven nano-frameworks for efficient colorectal cancer chemo-immunotherapy by suppression of cancer cell stemness

Cancer stemness, characterized by the self-renewal and differentiation capabilities of cancer stem cells (CSCs), is a critical determinant of colorectal cancer (CRC) chemo-immunotherapy. Herein, we repurposed copper-coordination driven metal-organic nano-frameworks (Cu-MOFs) to address the chemo-immunotherapy resistance posed by cancer stemness. These repurposed Cu-MOFs were loaded with the chemotherapeutic agent cisplatin (CDDP), resulting in the formation of Cu-MOF@CDDP. The Cu-MOF@CDDP are efficiently internalized by CRC cells via nanoparticle mediated endocytosis, where they release free copper ions (Cu2+) and CDDP in a high-glutathione (GSH) environment. After that, CDDP forms DNA-CDDP adducts that inhibit DNA synthesis and repair, while Cu2+ induces cuproptosis by disrupting mitochondrial metabolism. Moreover, DNA fragments originating from both the nucleus and mitochondria activate the cGAS-STING pathway, thereby initiating anti-tumor immune responses. Meanwhile, Cu2+ depletes intracellular GSH and induces cuproptosis, leading to the downregulation of stemness-related proteins such as ZEB1 and c-MYC, which enhances the efficacy of chemo-immunotherapy by targeting the critical pathways involved in maintaining stemness. Consequently, our results underscore the substantial promise of Cu-MOFs in overcoming stemness-driven therapeutic resistance, offering a transformative approach to sensitize chemo-immunotherapy.

Cuproptosis: mechanisms and nanotherapeutic strategies in cancer and beyond

Cuproptosis, a novel form of copper (Cu)-dependent programmed cell death, is induced by directly binding Cu species to lipoylated components of the tricarboxylic acid (TCA) cycle. Since its discovery in 2022, cuproptosis has been closely linked to the field of materials science, offering a biological basis and bright prospects for the use of Cu-based nanomaterials in various disease treatments. Owing to the unique physicochemical properties of nanomaterials, Cu delivery nanosystems can specifically increase Cu levels at disease sites, inducing cuproptosis to achieve disease treatment while minimizing the undesirable release of Cu in normal tissues. This innovative nanomaterial-mediated cuproptosis, termed as "nanocuproptosis", positions at the intersection of chemistry, materials science, pharmaceutical science, and clinical medicine. This review aims to comprehensively summarize and discuss recent advancements in cuproptosis across various diseases, with a particular focus on cancer. It delves into the biochemical basis of nanomaterial-mediated cuproptosis, the rational design for cuproptosis inducers, strategies for enhancing therapeutic specificity, and cuproptosis-centric synergistic cancer therapeutics. Beyond oncology, this review also explores the expanded applications of cuproptosis, such as antibacterial, wound healing, and bone tissue engineering, highlighting its great potential to open innovative therapeutic strategies. Furthermore, the clinical potential of cuproptosis is assessed from basic, preclinical to clinical research. Finally, this review addresses current challenges, proposes potential solutions, and discusses the future prospects of this burgeoning field, highlighting cuproptosis nanomedicine as a highly promising alternative to current clinical therapeutics.

Injectable copper ion cross-linked TEMPO-oxidized bacterial cellulose nanofiber hydrogels and their synergistic antimicrobial activity with glutathione

Microbial infections in deep wounds pose a major threat to human health. The development of hydrogel with both antimicrobial and injectable properties can effectively fill wounds while inhibiting microbial infections. In this study, we reported a copper ion cross-linked TEMPO-oxidized bacterial cellulose (OBC) nanofiber hydrogel. The dynamic nature of -COOH-Cu2+coordination imparted physicochemical versatility to Cu/OBC hydrogels, including injectability and optimal shear-thinning rheology. Duo to the Cu2+- mediated Fenton-like effect and its synergistic effect with glutathione (GSH), the obtained hydrogels could generate hydroxyl radical (·OH) and exhibited broad-spectrum antimicrobial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. Notably, the Cu/OBC/GHS hydrogel with low content of Cu2+ had good both hemolytic activity and cytocompatibility. Furthermore, the 2Cu/OBC/GSH10 hydrogel supported widespread cell attachment, improved cellular morphology, and enhanced viability, highlighting their potential as a biomaterial for sustained cell culture applications. This study provides a simple strategy to develop the injectable, antimicrobial, and biocompatible hydrogel.

Biomimetic Copper Nanozyme Reprograms Cold Tumor via Cuproptosis-Pyroptosis Crosstalk for Potent Renal Carcinoma Immunotherapy

Immune checkpoint blockade (ICB) therapy is an emerging strategy for renal cell carcinoma (RCC). However, its clinical efficacy remains constrained by its inherently poor immunogenicity and insufficient cytotoxic T lymphocyte (CTL) infiltration. Herein, we engineer a biomimetic copper nanozyme (Cu2O-OMV) by integrating Cu2O nanoparticles with bacterial outer-membrane vesicles (OMVs) to activate the antitumor immune response and synergize with ICB therapy. The Cu2O-OMV nanozyme exhibits peroxidase (POD)-like catalytic activity and releases Cu+ to exert Fenton-like activity, generating cytotoxic hydroxyl radicals (·OH) for tumor inhibition. Furthermore, Cu+ accumulation promotes the occurrence of cuproptosis, leading to the mitochondrial aggregation of lipoylated dihydrolipoamide S-acetyltransferase and depletion of ferredoxin 1. Notably, Cu2O-OMV concurrently activates pyroptosis via the noncanonical inflammasome pathway through its intrinsic lipopolysaccharide cargo, directly inhibiting tumor growth and inducing inflammatory cytokine release. The coordinated induction of cuproptosis and pyroptosis synergistically amplifies immunogenic cell death to enhance tumor immunogenicity, thereby promoting dendritic cell maturation and CTL infiltration. After combining with αPD-L1, it effectively destroys tumor cells to activate the antitumor immune response, thereby inhibiting tumor metastasis. Our study demonstrates a biomimetic nanozyme-driven strategy that harnesses dual cuproptosis-pyroptosis pathways to enhance the tumor immunogenicity and amplify the ICB efficacy, offering a transformative approach for RCC immunotherapy.

Self-assembled cysteine-copper chiral nanoparticles for inhibiting aggregation of amyloid β peptides

Inhibiting the aggregation of amyloid β (Aβ) peptides is a promising strategy for the treatment of Alzheimer's disease (AD). However, there have been very limited reports of highly effective inhibitors of Aβ aggregation in the past few decades. Herein, two types of nanoparticles (NPs) with opposite chirality were prepared through one-step assembly of L-cysteine (L-Cys) or D-cysteine (D-Cys) and Cu2+ at room temperature. L-Cys-Cu NPs and D-Cys-Cu NPs were able to inhibit the aggregation of Aβ42. Compared to their enantiomer L-Cys-Cu NPs, D-Cys-Cu NPs showed a larger binding affinity to Aβ42, leading to stronger inhibition of Aβ42 fibrillation. Moreover, D-Cys-Cu NPs were found to cause the disaggregation of Aβ42 fibrils. Due to their simple preparation, good biocompatibility and significant effects, these chiral Cys-Cu NPs have great potential in inhibiting protein aggregation.

Chiral-Dependent Redox Capacitive Biosensor Using Cu-Cys-GSH Nanoparticles for Ultrasensitive H2O2 Detection

Copper-thiolate nanostructures, formed through the self-assembly of cysteine (Cys) and glutathione (GSH) with copper ions, offer a versatile platform for redox-active applications due to their structural stability and chemical functionality. In this study, Cu-Cys-GSH nanoparticles were synthesized and employed to develop a capacitive biosensor for the ultralow concentration detection of hydrogen peroxide (H2O2). The detection mechanism leverages a Fenton-like reaction, where H2O2 interacts with Cu-Cys-GSH nanoparticles to generate hydroxyl radicals (·OH) through redox cycling between Cu2+ and Cu+ ions. These redox processes induce changes in the sensor's surface charge and dielectric properties, enabling highly sensitive capacitive sensing at gold interdigitated electrodes (IDEs). The influence of chirality on sensing performance was investigated by synthesizing nanoparticles with both L- and D-cysteine enantiomers. Comparative analysis revealed that the stereochemistry of cysteine impacts the catalytic activity and sensor response, with Cu-L-Cys-GSH nanoparticles exhibiting superior performance. Specifically, the biosensor achieved a linear detection range from 1.0 fM to 1.0 pM and demonstrated an ultra-sensitive detection limit of 21.8 aM, outperforming many existing methods for H2O2 detection. The sensor's practical performance was further validated using milk and saliva samples, yielding high recovery rates and confirming its robustness and accuracy for real-world applications. This study offers a disposable, low-cost sensing platform compatible with sustainable healthcare practices and facilitates easy integration into point-of-care diagnostic systems.

Innovative applications of silicon dioxide nanoparticles for targeted liver cancer treatment

Liver cancer remains a major global health challenge, characterized by high mortality and limited treatment efficacy. Conventional therapies, including chemotherapy, immunotherapy, and viral vectors, are hindered by systemic toxicity, drug resistance, and high costs. Silica nanoparticles (SiO2NPs) have emerged as promising platforms for liver cancer therapy, offering precise drug delivery, stimuli-responsive release, and integrated diagnostic-therapeutic capabilities. This review critically examines the potential of SiO2NPs to overcome these therapeutic limitations. Notable advances include their high drug-loading capacity, customizable surface modifications, and dual-responsive systems (pH/redox/NIR-II) that enable >90% tumor-specific drug release. Preclinical studies have demonstrated synergistic efficacy in combination therapies. Additionally, theranostic SiO2NPs enable MRI-guided tumor delineation and real-time treatment monitoring. Despite promising results, challenges remain in long-term biosafety, scalable synthesis, and regulatory compliance. Early-phase clinical trials, including those using NIR-II-responsive platforms, highlight their translational potential but underscore the need for further validation of toxicity profiles and manufacturing standards. Future research should focus on optimizing combinatory treatment strategies, scaling up production, and aligning with evolving regulatory frameworks. By bridging nanomaterial innovation with clinical applications, SiO2NPs offer unparalleled potential for advancing precision oncology in hepatocellular carcinoma.

Tumor-Specific On-Site Activation of Cisplatin via Cascade Catalytic-Redox Reactions for Highly Efficient Chemo-Immunotherapy

The therapeutic efficiency of platinum drugs is always limited by low utilization, side effects, and Pt-resistance. Herein, a double-lock protected PtII nanomedicine named PtNP@Cu has been developed, which performs cascade unlocking of dechlorinated cisplatin (DP) via catalytic-redox reactions, thus achieving tumor-specific "on-site" activation of cisplatin (cDDP) in the nucleus accompanied with substantial induction of ferroptosis of cancer cells. This design avoids the premature release of active PtII species in normal cells or in the cytoplasm of cancer cells before reaching nucleus, thereby ensuring maximum amplification of Pt-DNA crosslinking with tumor-specificity. Meanwhile, substantial GSH depletion and ROS production induced by cascade catalytic-redox reactions results in ferroptosis of cancer cells, which further reduces GSH-mediated cDDP detoxification, overcomes Pt-resistance, and enhances immunogenicity, ultimately realizing highly efficient tumor-specific chemotherapy and antitumor immunity in vivo. This work provides a new strategy for effectively and comprehensively addressing the issues of low utilization, side effects, and drug resistance problems of platinum drugs, which is also promising for chemo-immunotherapy.

One-Step Symbiosis of Bimetallic Peroxides Nanoparticles to Induce Ferroptosis/Cuproptosis and Activate cGAS-STING Pathway for Enhanced Tumor Immunotherapy

To improve the efficiency and application prospects of metal peroxides in tumor therapy, the synthesis of bimetallic peroxides via simple yet effective approaches will be highly significant. In this work, hyaluronic acid modified zinc-copper bimetallic peroxides (ZCPO@HA) nanoparticles are synthesized through a one-step symbiotic method by co-hydrolysis of zinc acetate and copper acetate in weakly alkaline solution, followed by modification with sodium hyaluronate. Upon decomposition in the tumor microenvironment, ZCPO@HA nanoparticles can generate a considerable content of hydroxyl radical (·OH) by Fenton-like reaction between Cu2+ and self-compensating hydrogen peroxide, while downregulating the expression of glutathione peroxidase 4 to induce ferroptosis. The abundant release of Cu2+ leads to the aggregation of dihydrolipoamide S-acetyltransferase and the reduction of iron-sulfur cluster proteins, causing cuproptosis. The immunogenic cell death of tumor cells releases abundant damage associated molecular patterns, effectively activating the adaptive immune response. Zn2+ and ·OH cause mitochondrial damage, leading to the release of a substantial amount of mitochondrial DNA. This subsequently activates the cyclic guanosine monophosphate-adenosine monophosphate synthase-stimulator of interferon genes (cGAS-STING) pathway, enhancing the innate immune response. In conclusion, it synthesizes a new type of bimetallic peroxides by one-step symbiosis for activating anti-tumor immunotherapy combined with immune checkpoint inhibitor.

A pH/STEAP Cascade-Responsive Nanomedicine with Self-Supplied Peroxide for Precise Chemodynamic Therapy

Self-supply of peroxo compounds has been regarded as a promising strategy to enhance Fenton chemistry-based chemodynamic therapy (CDT). However, the inherent selectivity of CDT will be affected after introducing peroxide-supplementing functionality into chemodynamic agents due to the lack of ability to distinguish cancer cells from normal cells. Here, an intelligent CDT nanomedicine is reported with both cascade-responsive and peroxide self-supplying performances for specific and efficient cancer treatment. Upon endocytosis into acidic endo/lysosomes, the CDT nanomedicine comprising methyl linoleate hydroperoxide (MLH)-loaded amorphous iron oxide nanoparticles (AIO@MLH NPs) can be decomposed to release MLH and Fe3+ that is further reduced into Fe2+ by endo/lysosomal six-transmembrane epithelial antigen of the prostate (STEAP) with metalloreductase activity, enabling the occurrence of Fenton-type reaction between high-active Fe2+ and MLH for free radical generation, which causes endo/lysosomal damage and cancer cell apoptosis. Noteworthily, AIO@MLH NPs exhibit potent chemodynamic cytotoxicity to cancerous cells rather than non-cancerous cells benefiting from the overexpressed STEAP in multiple cancers, thereby leading to precise tumor CDT. This work highlights the use of endogenous STEAP to improve the selectivity of peroxide self-supplying chemodynamic agents and paves the way for the development of precision medicine.

Glucose oxidase/copper‑carbon dots/hyaluronic acid self-assembly for self-supply hydrogen peroxide in a double-enzyme cascade to enhance anti-tumor therapy

Although chemodynamic therapy (CDT) has proven to be a promising anti-tumor strategy, its efficacy is limited by the insufficient supply of H2O2 in tumor tissues. To solve the problem of insufficient H2O2, in this paper, a novel double-enzyme cascade nanoreactor hyaluronic-cinnamaldehyde Schiff base@glucose oxidase (GOx)/copper doped carbon dot (abbreviation HCFCTG), which constructed by co-assembly of copper doped carbon dot (CuFACDs-TPP), glucose oxidase (GOx) and hyaluronic-cinnamaldehyde Schiff base (HA-CA) was designed for the first time. The HCFCTG released GOx and CuFACDs-TPP under pH stimulation. GOx continues to supply H2O2 to CDT by consuming glucose, while cutting off the supply of nutrients to starve cancer cells to death (ST), ultimately amplifying the therapeutic effect of CDT. CuFACDs-TPP precisely anchors mitochondria to destroy mitochondria and induce apoptosis, while copper ions consume glutathione to amplify reactive oxygen species (ROS) levels. Self‑oxygenation of HCFCTG by Fenton-like reaction down-regulates hypoxia-inducible factor (HIF-1α) to consolidate CDT effect. The 808 nm laser activates the photothermal effect enhances CDT. In vitro and in vivo experiments proved that HCFCTG has good biocompatibility and excellent CDT effect. HCFCTG overcomes the problem of insufficient H2O2 in the CDT process.

Biomimetic Cascade Nanozyme Catalytic System for the Treatment of Lymph Node Metastasis in Gastric Cancer

Lymphatic metastasis of gastric cancer is a challenging issue in clinical practice. Recently, copper single-atom nanozymes (SAZ) have gained tremendous attention due to its superior peroxidase (POD) activity that has good nonocatalytic tumor therapy (NCT) capabilities, and photothermal properties. Therefore, using a high-expressing P-selectin platelet membrane (PM) to encapsulate SAZ and cisplatin is proposed, forming PSC nanoparticles. Due to their exquisite nanoscale size and the unique structure of lymphatic vessels, PSC can highly target cancer cells in invasive primary tumors and metastatic lymph nodes that both highly express CD44. It is noteworthy that cisplatin can simultaneously perform chemotherapy and generate H₂O₂ under the action of NADPH oxidases (NOXs) that further enhance the catalytic activity of SAZ and increase intracellular reactive oxygen species (ROS) production. Both in vitro and vivo experiments have demonstrated the superior targeting and elimination capability of the PCS system in primary and metastatic tumor cells. In addition, transcriptomic analysis reveals that PSC + NIR induced apoptosis in MFC cells. This marks the first proposal of combining single-atom nanozymes and chemotherapy drugs for dual-targeting in gastric cancer and lymphatic metastasis, providing new insights into a challenging clinical issue in the treatment of gastric cancer lymphatic metastasis.

A Copper-Based Photothermal-Responsive Nanoplatform Reprograms Tumor Immunogenicity via Self-Amplified Cuproptosis for Synergistic Cancer Therapy

Studies show that intracellular accumulation of copper ions causes cuproptosis, potentially enhancing anticancer immunity. However, the induction of cuproptosis inevitably faces challenges due to low intracellular copper deliver efficiency and collateral damage to normal tissues. This paper presents a self-amplified cuproptosis nanoplatform (CEL NP) composed of Cu2- XS hollow nanospheres (HNSs), elesclomol (ES), and phase-change material lauric acid (LA). Under NIR-II laser irradiation, the photothermal energy generated by Cu2- XS HNSs melts LA, facilitating the precise release of ES and copper ions within the tumor microenvironment. Notably, ES can traverse the cell membrane and form ES-Cu(II) complexes, thereby enhancing copper delivery within tumor cells. Excess Cu(II) also reacts with endogenous glutathione, reducing its inhibitory effect on cuproptosis. Ultimately, this amplified cuproptosis effect can activate immunogenic cell death, eliciting a robust immune response and promoting tumor suppression. The CEL NP-mediated release of ES and copper ions offers a novel approach for anticancer therapy through cuproptosis induction.

Bimetallic chitosan/hyaluronic acid nanoparticles self-amplify ferroptosis/cuproptosis in triple-negative breast cancer

As a notoriously incurable tumor, triple-negative breast cancer (TNBC) exhibits significant sensitivity to ferroptosis and the glutathione (GSH) antioxidant defense system plays a crucial role in its progression. Herein, we report a bimetallic chitosan/hyaluronic acid nanoparticle (5FCN, with a Fe/Cu mass ratio of 5:5) that employs a self-amplified dual mechanism of ferroptosis and cuproptosis for TNBC therapy. Hyaluronic acid in 5FCN specifically binds to the overexpressed CD44 receptor on TNBC cells. This allows 5FCN to enter cells via receptor-mediated endocytosis, then release metal ions in acidic environments. Released Fe3+ and Cu2+ react with GSH in tumor cells, weakening the antioxidant system and producing Fe2+ and Cu+. These ions trigger Fenton/Fenton-like reactions with H2O2, generating toxic hydroxyl radicals (·OH) to boost ferroptosis. Meanwhile, high-valent Cu2+ and Fe3+ are produced, forming a cycle for GSH depletion and ·OH generation. As H2O2 depletes, the rising Cu+ level in cells causes lipoylated protein aggregation, amplifying cuproptosis. In vitro and in vivo studies demonstrated that 5FCN exhibited superior cell-killing efficacy against TNBC with few side effects. Collectively, 5FCN represents a potential drug to self-amplify ferroptosis/cuproptosis in TNBC.

Self-targeted nanosystem for enhanced chemodynamic cancer therapy

Chemodynamic therapy (CDT) could have a significant potential for advancing cancer treatment via the utilization of Fenton and Fenton-like reactions, which produce toxic reactive species. Nonetheless, the efficacy of CDT is constrained by the limited availability of catalyst ions capable of decomposing pre-existing intracellular H2O2 and generating reactive oxygen species (ROS) necessary to achieve a therapeutic response. To address these limitations, a tailored strategy has been developed to enhance the efficacy of Fenton-like reactions to eradicate selectively cancer cells. This innovative approach involves the utilization of dual metal cations (Zn2+, Fe2+) within zinc nitroprusside (ZnNP) material. Remarkably, this method takes advantage of the acidic conditions prevalent in tumors, thus eliminating the need for external stimuli. Through these advancements, the tailored approach exhibits the potential to specifically target and eliminate cancer cells, overcoming the mentioned limitations. A simple mixing technique was utilized to synthesize ZnNP, which was structurally and morphologically characterized. Furthermore, extensive in vitro investigations were conducted to assess its anti-tumoral mechanism of action. ZnNP exhibits a remarkable capability to increase intracellular H2O2 within cells. This process leads to the generation of various reactive species, including hydroxyl (˙OH) and superoxide (O2˙-) radicals, and peroxynitrite (ONOO-), which act as apoptotic inducers specifically targeting cancer cells. Cellular uptake studies have shown that ZnNP enters the lysosomes, evades degradation, and takes advantage of their acidic pH environment to significantly increase the production of ROS. These findings are further supported by the activation of multiple oxidative genes. Furthermore, the biocompatibility of ZnNP has been demonstrated in ex vivo models using healthy liver cells. Notably, ZnNP exhibited therapeutic effectiveness in high-grade serous ovarian cancer (HGSOC) patient-derived tumor organoids (PDTO), further confirming its potential as a therapeutic agent. The present study highlights the therapeutic potential of ZnNP as a generator of multiple ROS via a Fenton-like reaction. This research offers a promising therapeutic approach for CDT application in combatting HGSOC, a highly aggressive and life-threatening cancer.

A novel nanomedicine for osteosarcoma treatment: triggering ferroptosis through GSH depletion and inhibition for enhanced synergistic PDT/PTT therapy

Osteosarcoma treatment remains challenging due to the limitations of single-modality therapies. To address this, we designed a carrier-free nanomedicine SRF@CuSO4.5H2O@IR780 (CSIR) for synergistic ferroptosis, photodynamic therapy (PDT), and photothermal therapy (PTT) in osteosarcoma. Interestingly, CSIR could harness the enhanced permeability and retention (EPR) effect to effectively enter tumors. Copper ions (Cu2+) within CSIR could react with the reductive intracellular environment, depleting glutathione (GSH) levels. Near-infrared (NIR) irradiation of CSIR further depleted GSH through reactive oxygen species (ROS) generation. Additionally, CSIR released sorafenib (SRF), which inhibited cystine-glutamate antiporter system xCT (xCT), thereby blocking GSH biosynthesis. RNA sequencing data confirmed ferroptosis induction by CSIR. This synergistic strategy of GSH depletion-induced ferroptosis, enhanced PDT, and photothermal cascade holds promise for improved osteosarcoma treatment and future nanomedicine design.

Bioactive metal sulfide nanomaterials as photo-enhanced chemodynamic nanoreactors for tumor therapy

Metal sulfide nanomaterials (MeSNs) are highly promising for biomedical applications due to their low toxicity, good dispersibility, high stability, adjustable particle sizes, and good biocompatibility. Their unique chemical and light-conversion properties also enable them to function as photothermal or photodynamic agents, enhancing chemodynamic therapy (CDT) of tumors. This makes MeSNs valuable as photo-enhanced CDT nanoagents, advancing precision and multi-modal tumor treatment. This review examines recent advancements in MeSNs for photo-enhanced chemodynamic tumor ablation, comparing their effectiveness in CDT. It highlights the roles of photothermal, photodynamic, and photocatalytic effects in enhancing treatment efficacy. MeSN-based nanoreactors are categorized by composition into iron sulfide, copper sulfide, other unary, and multi-MeSNs for their applications in tumor therapy. Additionally, this review discusses challenges, limitations, and future biomedical applications of MeSNs, offering insights into their potential for next-generation cancer treatments.

Hydrogel-enabled ROS-GSH modulation for sustained copper-mediated chemodynamic therapy of oral squamous cell carcinoma

Copper ion (Cu2+) has been revealed to be involved in the occurrence and development of oral squamous cell carcinoma (OSCC), making copper-mediated chemodynamic therapy (Cu-CDT) a promising treatment strategy for OSCC by elevating Cu2+ levels to generating a large amount of reactive oxygen species (ROS). However, the excessive reduced glutathione (GSH) in the tumor microenvironment can scavenge the ROS generated by Cu-CDT. While the directional co-delivery of Cu2+ and GSH-depleting agents shows promise for Cu-CDT in OSCC therapy, their rapid metabolism and the superficial nature of OSCC lesions necessitate tailored drug formulations to ensure effective bioavailability. To counteract this challenge, this work proposed a practical hydrogel-supported ROS-GSH regulation strategy, which involves the on-demand design of a copper ion-crosslinked guanosine-based hydrogel (GCD) containing dimethyl fumarate (DMF, which conjugates with GSH for consumption). It can directionally and sustainably co-deliver Cu2+ and DMF to OSCC lesions under mildly acidic pH conditions, thereby enhancing Cu-CDT efficiency through improved Cu2+ utilization and DMF-driven GSH depletion. As anticipated, the strategy sustains the generation of hydroxyl radicals, effectively inducing apoptosis and suppressing cell proliferation in CAL-27 cells, which consequently inhibits the growth of OSCC tumors. Therefore, this work highlights the GCD hydrogel's great potential as a promising Cu-CDT therapeutic platform.

Engineering Dual-Responsive Nanoplatform Achieves Copper Metabolism Disruption and Glutathione Consumption to Provoke Cuproptosis/Ferroptosis/Apoptosis for Cancer Therapy

Cuproptosis is a new copper-dependent form of regulated cell death and shows enormous promise in cancer therapy. However, its therapeutic performance is compromised by the strictly regulated copper metabolism and highly expressed intracellular glutathione (GSH). Herein, an intelligent nanoplatform (NSeMON-P@CuT/LipD) is rationally developed as a copper metabolic disrupter, GSH consumer, and Fenton-like reaction trigger for cancer cuproptosis/ferroptosis/apoptosis therapy. NSeMON-P@CuT/LipD is constructed from the preparation of diselenide-bridged mesoporous organosilica nanoparticles, and then pemetrexed (Pem) is loaded followed by surface deposition with a Cu2+-3,3'-dithiobis(propionohydrazide) (TPH) coordinated network and coating with a diclofenac (DC)-encapsulated liposome. In response to the specific tumor microenvironment, the obtained NSeMON-P@CuT/LipD can release DC, Cu2+, and Pem and simultaneously amplify cellular oxidative stress by consuming GSH and catalyzing endogenous H2O2 into hydroxyl radicals (•OH). Both liberated DC and augmented oxidative stress can inhibit glycolysis, reduce ATP level, and then block copper transporter ATP7B, resulting in metabolic disorders and the high retention of copper in cells for •OH generation. Moreover, the overloaded copper can promote dihydrolipoamide S-acetyltransferase oligomerization and Fe-S cluster protein loss, thus evoking cuproptosis. Collectively, the augmented oxidative stress activates prominent ferroptosis, which cooperates with cuproptosis and Pem-mediated apoptosis to significantly inhibit the tumor growth of 4T1 tumor-bearing mice. This study demonstrates feasible strategies to enhance tumor cuproptosis using a single nanoplatform and may also inspire the design of advanced cuproptosis-related therapies.

A Highly-Active Chemodynamic Agent Based on In Situ Generated Copper Complexes from Copper Hexacyanoferrate Nanoparticles

Copper hexacyanoferrate (Cu2Fe(CN)6) nanocubes with a homogeneous size under 100 nm are synthesized by self-assembly from Cu2+ and Fe(CN)6 3- precursors. Similar to previous reports with catalysts containing Cu and Fe, the objective is to produce a nanoparticle catalyst that can promote glutathione (GSH) oxidation thanks to the Cu contribution, plus some ROS production through Fenton-like processes fostered by Fe. Unexpectedly, the catalytic activity for GSH oxidation are much higher (≈50%) than those obtained with equal Cu amounts provided as CuCl2. Furthermore, in the presence of GSH concentrations characteristic of the tumor microenvironment, the nanocubes disassembled homogeneously, without a noticeably change of composition. These results suggest that this strong increase of catalytic activity arises from synergistic coordination of the released Cu2+ and Fe(CN)6 3- ions that facilitate GSH deprotonation, accelerating its oxidation. Given the role of GSH in the nanoparticle disassembly process, a selective action of the catalyst can be obtained: lethal doses as low as 18 ppm of Cu are obtained for U251-MG cancer cells while healthy fibroblasts are largely spared.

Biomineralization of Copper-Celastrol Nanohybrids for Synergistic Antitumor Therapy

The therapeutic potential of celastrol (Cel) in cancer treatment has been constrained by its intrinsic hydrophobicity and the lack of efficient delivery systems. Herein, a biomineralization-based strategy is introduced to construct hybrid nanoparticles (Cel-TA-Cu NP) via Cel-Cu2⁺ coordination, followed by TA-Cu2⁺ crosslinking. Biomineralization, a nature-inspired process facilitating the controlled assembly of inorganic-organic structures, enables Cel to form coordination complexes with Cu2⁺, which subsequently serve as nucleation sites for tannic acid-mediated copper mineralization. Unlike conventional nanocarriers, this approach exploits the intrinsic metal-binding capacity of Cel to induce spontaneous mineralization, where Cu2⁺ serves both as a coordination center for drug encapsulation and as a therapeutic agent for chemodynamic therapy (CDT). The pH-responsive dissociation of metal-phenolic coordination ensures tumor-specific drug release, while the biomineralization process inherently enhances aqueous stability and bioavailability. Moreover, the rational design of Cel-TA-Cu NP enables a synergistic anticancer effect by simultaneously triggering apoptotic signaling pathways and amplifying oxidative stress-induced cytotoxicity. Overall, this biomineralization-based nanoplatform not only overcomes the inherent limitations of Cel but also integrates CDT to markedly enhance therapeutic efficacy, providing a promising avenue for advanced cancer treatment.

Bimetallic peroxide-based nanotherapeutics for immunometabolic intervention and induction of immunogenic cell death to augment cancer immunotherapy

Immunotherapy has transformed cancer treatment, but its efficacy is often limited by the immunosuppressive characteristics of the tumor microenvironment (TME), which are predominantly influenced by the metabolism of cancer cells. Among these metabolic pathways, the indoleamine 2,3-dioxygenase (IDO) pathway is particularly crucial, as it significantly contributes to TME suppression and influences immune cell activity. Additionally, inducing immunogenic cell death (ICD) in tumor cells can reverse the immunosuppressive TME, thereby enhancing the efficacy of immunotherapy. Herein, we develop CGDMRR, a novel bimetallic peroxide-based nanodrug based on copper-cerium peroxide nanoparticles. These nanotherapeutics are engineered to mitigate tumor hypoxia and deliver therapeutics such as 1-methyltryptophan (1MT), glucose oxidase (GOx), and doxorubicin (Dox) in a targeted manner. The design aims to alleviate tumor hypoxia, reduce the immunosuppressive effects of the IDO pathway, and promote ICD. CGDMRR effectively inhibits the growth of 4T1 tumors and elicits antitumor immune responses by leveraging immunometabolic interventions and therapies that induce ICD. Furthermore, when CGDMRR is combined with a clinically certified anti-PD-L1 antibody, its efficacy in inhibiting tumor growth is enhanced. This improved efficacy extends beyond unilateral tumor models, also affecting bilateral tumors and lung metastases, due to the activation of systemic antitumor immunity. This study underscores CGDMRR's potential to augment the efficacy of PD-L1 blockade in breast cancer immunotherapy.

Immunostimulatory Hydrogel with Synergistic Blockage of Glutamine Metabolism and Chemodynamic Therapy for Postoperative Management of Glioblastoma

Glioblastoma multiforme (GBM) is one of the most lethal malignant brain tumors in the central nervous system. Patients face many challenges after surgery, including tumor recurrence, intracranial pressure increase due to cavitation, and limitations associated with immediate postoperative oral chemotherapy. Here an injected peptide gel with in situ immunostimulatory functions is developed to coordinate the regulation of glutamine metabolism and chemodynamic therapy for overcoming these postoperative obstacles. The methodology entails crafting injectable gel scaffolds with short peptide molecules, incorporating the glutaminase inhibitor CB-839 and copper peptide self-assembled particles (Cu-His NPs) renowned for their chemodynamic therapy (CDT) efficacy. By fine-tuning glutamic acid production via metabolic pathways, this system not only heightens the therapeutic prowess of copper peptide particles in CDT but also escalates intracellular oxidative stress. This dual mechanism culminates in augmented immunogenic cell death within glioblastoma multiforme cells and improves a conducive immune microenvironment. Based on the concept of metabolic reprogramming, this treatment strategy has great potential to significantly reduce GBM tumor recurrence and prolong median survival in murine models.

Composite bioreactor for synergistic Modulation of tumor microenvironment and endogenous Regulation of ROS generation to enhance chemodynamic therapy for lung cancer

The tumor microenvironment (TME) is characterized by several key features, including hypoxia, elevated levels of hydrogen peroxide (H2O2), high concentrations of glutathione (GSH), and an acidic pH. Recent research has increasingly focused on harnessing or targeting these characteristics for effective cancer therapy. In this study, we developed an innovative composite bio-reactor that integrates genetically engineered bacteria with upconversion nanoparticles (UCNPs) and nano-copper manganese materials for lung cancer treatment. The nano-copper manganese materials function as catalysts in Fenton-like reactions, facilitating the decomposition of hydrogen peroxide into harmful hydroxyl radicals and oxygen, which can effectively target tumors and reduce hypoxia. To circumvent the challenge of insufficient endogenous hydrogen peroxide during treatment, we employed UCNPs capable of converting near-infrared laser irradiation, known for its deep tissue penetration, into visible light. This conversion activates the genetically engineered bacteria to generate exogenous hydrogen peroxide directly within the tumor microenvironment, enabling prolonged therapeutic effects. Our findings suggest that this composite bio-reactor can achieve effective lung cancer therapy without the need for external hydrogen peroxide supplementation, representing a significant advancement in the design of targeted cancer treatments.

Carrier-free nanoparticles based on self-assembly of 5-FU and copper-genistein complexes for the combined treatment of hepatocellular carcinoma

5-Fluorouracil (5-FU) is commonly used as a chemotherapeutic drug for advanced HCC. However, the effectiveness of 5-FU is limited by the emergence of resistance and poor targeting efficiency. Combining 5-FU with natural compounds has shown promise in HCC treatment. In this study, we prepared carrier-free nanoparticles (GEN-Cu-GEN@FUA) containing 5-FU and genistein (GEN) in a synergistic ratio via a green synthesis procedure. The resulting GEN-Cu-GEN@FUA nanoparticles had a spherical or near spherical shape, a dynamic size of 129.3 ± 40.1 nm, and a high drug loading content of approximately 21.40% (5-FU) and 61.48% (GEN). These nanoparticles exhibited approximately 3.6-fold lower IC50 value than 5-FU alone in Bel-7402 cells and resulted in a 3.7-fold greater reduction in tumor weight compared to 5-FU alone in Bel-7402 tumor-bearing BALB/c mice. Importantly, the nanoparticles showed negligible systemic toxicity due to their synergistic effect on cancer cell dysfunction and significant amplification of intracellular glutathione consumption. Our findings suggest that the developed carrier-free nanomedicines offer a highly promising platform for the co-delivery of genistein (GEN) copper(II) complexes and 5-FU, with easy fabrication and great potential for clinical translation in HCC synergistic therapy.

Dual-mode strategy for the determination of vanillin in milk-based products based on molecular-imprinted nanozymes

The inclusion of artificial food additives such as vanillin in infant formula should be strictly monitored to mitigate potential negative impacts on the dietary habits and health of infants. This raises a necessity of an accurate inspection and prompt feedback of vanillin in infant foods. In this study, colorimetric and fluorescent dual-mode assays based on CuNS/Fe3O4@MIPs were established to detect vanillin selectively and sensitively. Quantification of vanillin could be achieved with linear detection ranges of 1-100 μM and 1-150 μM for the colorimetric and fluorescent assays respectively. The corresponding detection limits were 0.11 and 0.10 μM respectively. The CuNS/Fe3O4@MIPs-based dual-mode assays exhibited good selectivity and stability for vanillin detection in infant formula and milk-based foods. Hence, this method can serve as a reliable tool for the cost-saving, effective and quantitative determination of vanillin in infant foods, with the potential to replace conventional instrumental analysis.

Preparation of Quercetin/Copper Nanoparticles and Their Preservation Performance on Shine Muscat Grapes

Deterioration in fruits represent a significant challenge to food safety, which has prompted our investigation into sustainable fruit preservation technologies. This paper presents the synthesis of quercetin/copper nanoparticles (QC NPs) and their application in the preservation of Shine Muscat grapes. The QC NPs, prepared through quercetin/copper complexation, exhibited stability with a particle size of 79.4 ± 3.2 nm and a zeta potential of -34.00 ± 4.98 mV. The nanoparticles exhibited robust antioxidant activity and 100% bactericidal effect against E. coli and S. aureus at 0.05 mg/mL, thereby underscoring their potential for use in fruit preservation. The application of a sodium alginate (SA) + QC NP coating to Shine Muscat grapes resulted in an 8.08% reduction in weight loss in comparison to the control, which exhibited a 10.40% reduction. The coating maintained firmness and preserved titratable acid content, thereby extending the storage life of the grapes. These findings position QC NPs as a promising material in eco-friendly and effective fruit preservation, and offer a viable solution to postharvest fruit preservation.

Substrate Specificity of Adenine-Cu-PO4 Nanozyme: Ascorbic Acid Oxidation and Selective Cytotoxicity

Though nanozymes are becoming promising alternatives to natural enzymes due to their superior properties, constructing nanozyme with high specificity is still a great challenge. Herein, with Cu2+ as an active site and adenine as a ligand, Adenine-Cu-PO4 is synthesized in phosphate-buffered saline. As an oxidase mimic, Adenine-Cu-PO4 could selectively catalyze oxidation of ascorbic acid (AA) to dehydroascorbic acid, but not universal substrates (3,3',5,5'-tetramethylbenzidine (TMB), 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and 2,4-dichlorophenol (2,4-DP)), small biomolecules (dopamine, glutathione, glucose, galactose), other vitamins (vitamin A acid, vitamin B1, vitamin K1) and even dithiothreitol (a common interference of AA). Such the specific AA catalytic oxidation is revealed that Adenine-Cu-PO4 selectively binds with AA through hydrogen bonds, accompanied with catalyzing AA oxidation, and concurrently O2 transferring to H2O2 via O2⋅-, further to H2O via ⋅OH. Based on the produced reactive oxygen species, with AA as a pro-oxidant, Adenine-Cu-PO4 nanozyme efficiently triggers severe intratumor oxidative stress to induce tumor cell death. This work opens a new avenue to design intrinsic nanozymes with high specificity, and also presents a promising application in the field of AA oxidation induced cancer therapy.

Recent advances in chemodynamic nanotherapeutics to overcome multidrug resistance in cancers

Multidrug resistance (MDR) has become a major challenge in cancer therapy, it results in the failure of chemotherapy and anticancer drug development. Chemodynamic therapy (CDT), an emerging cancer treatment strategy, has been reported as a novel approach for cancer treatment characterized by low toxicity and minimal side effects. By generating robust cytotoxic hydroxyl radicals (·OH) via Fenton/Fenton-like reaction, CDT may cause cellular damage and oxidative stress-induced cell death. In recent years, many therapies based on CDT and/or combined with other treatment modalities are reported and exhibit exciting treatment efficacy in cancer treatment, such as photothermal therapy, photodynamic therapy, sonodynamic therapy, chemotherapy, starvation therapy and gas therapy etc. These combination therapies exhibit synergistic effects, significantly improving anticancer outcomes compared to CDT alone. Herein, we provide a comprehensive overview of CDT-based strategies in cancer treatment, highlighting developments of CDT and CDT-based combination strategies in tumor therapy, especially in overcoming MDR challenges. Finally, the opportunities and challenges of CDT and CDT-combination therapy in the clinical application are also addressed.

Anti-Tumor Strategies Targeting Nutritional Deprivation: Challenges and Opportunities

Higher and richer nutrient requirements are typical features that distinguish tumor cells from AU: cells, ensuring adequate substrates and energy sources for tumor cell proliferation and migration. Therefore, nutrient deprivation strategies based on targeted technologies can induce impaired cell viability in tumor cells, which are more sensitive than normal cells. In this review, nutrients that are required by tumor cells and related metabolic pathways are introduced, and anti-tumor strategies developed to target nutrient deprivation are described. In addition to tumor cells, the nutritional and metabolic characteristics of other cells in the tumor microenvironment (including macrophages, neutrophils, natural killer cells, T cells, and cancer-associated fibroblasts) and related new anti-tumor strategies are also summarized. In conclusion, recent advances in anti-tumor strategies targeting nutrient blockade are reviewed, and the challenges and prospects of these anti-tumor strategies are discussed, which are of theoretical significance for optimizing the clinical application of tumor nutrition deprivation strategies.

DNA-mediated self-assembly oxidative damage amplifier combined with copper and MTH1 inhibitor for cancer therapy

Chemo-dynamic therapy (CDT) has a great potential in tumor extirpation. It entails producing hypertoxic reactive oxygen species (ROS) that damage the DNA of tumor cells and other biomacromolecules. However, the efficiency of CDT is severely hampered by the massive presence of glutathione (GSH) in tumor cells and the interference of ROS defense systems, such as Mutt homolog 1 (MTH1) protein sanitizes ROS-oxidized nucleotide pools. In this research, DNA-mediated self-assembly nanoparticles (HTCG@TA NPs) were engineered with high-performance amplified oxidative damage and gene therapy effect for synergistic anti-tumor treatment. Cu2+ was converted into Cu + by redox reactions to deplete GSH while H2O2 was catalyzed to generate hydroxyl radicals (·OH). As a result, the ROS level was evidently improved. Moreover, controllable-released TH588 prevented MTH1-mediated DNA repairing, thus aggravated oxidative damage to tumor cells. Meanwhile, the released functional nucleic acid G3139 downregulated the expression of Bcl-2, and accelerated the apoptosis of tumor cells. In conclusion, the HTCG@TA demonstrated significant effect in oxidative damage amplification and tumor inhibition both in vitro and in vivo, which has provided a new outlook for the clinical application of chemo-dynamic tumor treatment and synergistic gene therapy with self-delivery nanoplatforms.

Advances in cuproptosis harnessing copper-based nanomaterials for cancer therapy

Cuproptosis, a newly identified programmed cell death form, is characterized by excessive copper accumulation in cells, resulting in mitochondria damage and toxic protein stress, ultimately causing cell death. Given the considerable therapeutic promise of copper toxicity in cancer treatment, copper-based nanomaterials that induce copper death have attracted interest as a promising approach for tumor therapy. This review comprehensively introduces the mechanisms of cuproptosis and the associated regulatory genes, including both positive and negative regulatory regulators, and systematically summarizes the application of various nanoparticles in inducing cuproptosis, ranging from inorganic copper compounds to delivery systems. These nanoparticles offer significant advantages, such as improving copper absorption, extending the duration of effectiveness, enhancing the precision of copper release, increasing biocompatibility, and serving as enhancers in combination therapy. In conclusion, the authors present a detailed overview and insights into the current research directions of nanoplatforms that facilitate copper-induced cancer treatment, establishing a foundation for the future development of effective nanomedicines that induce cuproptosis and offering new possibilities and treatment strategies for tumor therapy.

Supramolecular Nanozymes Based on Self-Assembly of Biomolecule for Cancer Therapy

Natural enzyme systems possess extraordinary functions and characteristics, making them highly appealing for use in eco-friendly technologies and innovative cancer treatments. However, their inherent instability and structural complexity often limit their practical applications, leading to the exploration of biomolecular nanozyme alternatives. Supramolecular nanozymes, constructed using self-assembly techniques and various non-covalent interactions, have emerged as a promising solution. Amino acids, peptides, and protein motifs offer flexible building blocks for constructing these nanozymes. Importantly, the well-defined structural regulation mechanisms of biomolecular nanozymes, along with their unique properties as fundamental biological modules in living systems-such as selectivity, permeability, retention, and biocompatibility-present new opportunities for cancer therapy. This review highlights recent advances in supramolecular self-assembled nanozymes, including peroxidases, oxidases, catalases, superoxide dismutases, and other nanozyme systems, as building blocks for tumor therapy. Additionally, it discusses precise functional modulation through supramolecular non-covalent interactions and their therapeutic applications in targeting the tumor microenvironment. These studies provide valuable insights that may inspire the design of novel supramolecular nanozymes with enhanced catalytic selectivity, biocompatibility, and tumor-killing efficacy.

Piezoelectric-mediated two-dimensional copper-based metal-organic framework for synergistic sonodynamic and cuproptosis-driven tumor therapy

Sonodynamic therapy (SDT) is a minimally invasive therapeutic approach that utilizes sonosensitizers to catalyze substrates and generate reactive oxygen species (ROS) under ultrasound stimulation, ultimately inducing tumor cell death. Enhancing the piezoelectric properties of nanomaterials and modulating the semiconductor energy band are effective strategies to improve the catalytic efficiency of sonosensitizers. In this study, we developed a two-dimensional (2D) copper-based piezoelectric metal-organic framework (MOF) sonosensitizer, denoted as CM, through the coordination of copper and dimethylimidazole. The unique 2D MOF structure imparts CM with piezoelectric characteristics, enabling it to enhance SDT efficacy by modulating the semiconductor bandgap and carrier mobility. Upon ultrasound irradiation, CM catalyzes oxygen to undergo a cascade reaction, producing highly toxic singlet oxygen. Additionally, cupric ions in CM can be reduced by glutathione, facilitating the spontaneous catalysis of hydrogen peroxide in tumors to generate hydroxyl radicals and deplete glutathione, thereby inducing oxidative damage. Moreover, cupric ions in CM can trigger tumor cell cuproptosis, which, in combination with the generated ROS, accelerates cell death. Thus, this study establishes a MOF-based system for controllably inducing multi-pathway cancer cell death and provides a foundation for enhancing ultrasound-catalyzed tumor therapy through the optimization of piezoelectric properties.

GSH/pH-responsive copper-based cascade nanocomplexes inducing immunogenic cell death through cuproptosis/ferroptosis/necroptosis in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) remains a formidable challenge due to high recurrence rates and limited efficacy of conventional treatments. Immunotherapy holds potential, but its effectiveness is often restricted by low patient responsiveness. This study presents a novel therapeutic strategy using GSH/pH-responsive copper-based cascade nanocomplexes to induce immunogenic cell death (ICD) in OSCC. The fabricated nanocomplex, PC@B-H, leverages the acidic and reducing tumor microenvironment to release copper ions and plumbagin, triggering a cascade of cell death mechanisms including cuproptosis, ferroptosis, and necroptosis. This multifunctional system not only enhances oxidative stress but also depletes glutathione, promotes lipid peroxidation, and disrupts mitochondrial function, leading to robust tumor inhibition. Additionally, the induction of ICD facilitates dendritic cell maturation and cytotoxic T lymphocyte infiltration, providing durable anti-tumor immunity. The study demonstrates that PC@B-H achieves a 92.3 % tumor growth inhibition rate with minimal systemic toxicity, offering a promising avenue for enhancing the efficacy of OSCC treatment through combined cell death pathways and immune activation.

Sequential Therapy for Osteosarcoma and Bone Regeneration via Chemodynamic Effect and Cuproptosis Using a 3D-Printed Scaffold with TME-Responsive Hydrogel

Post-surgical recurrence and extensive bone defects pose significant challenges during osteosarcoma treatment. These issues can be addressed using a novel strategy that promotes bone repair after removing residual tumors. Therefore, a 3D-printed porous polylactic acid (PLA) scaffold (PH-GBS@CCP) filled with hydrogel and surface-modified with nano-hydroxyapatite (nHA) is designed. The hydrogel, composed of gelatin modified with methacrylic anhydride (GelMA), sodium alginate (SA), and borax, contains Cu-Cys-PEG nanoparticles (CCP) modified with cRGDfk-PEG2K-DSPE. It is injected into the PLA scaffold and crosslinked under UV. This hydrogel acts as a buffer medium between scaffold and bone, reducing cell abrasion, and as a carrier for the responsive release of tumor-targeting CCP. The scaffold provides the support and microenvironment required for bone repair. In early treatment, the acidic tumor microenvironment promotes hydrogel disintegration and CCP release, depleting glutathione and converting Cu2+ to Cu+ for the Fenton-like reaction. This generates reactive oxygen species, strengthening the proptosis effect, and killing the tumor. In later treatment, after tumor elimination, normalized pH and slow CCP release, along with scaffold nHA, promote osteogenic differentiation, providing a sustained osteogenic effect. Overall, the multifunctional composite scaffold achieved the sequential management of post-surgical osteosarcoma through early tumor-killing and later osteogenic effects.

A pH/GSH Dual-Responsive Triple Synergistic Bimetallic Nanocatalyst for Enhanced Tumor Chemodynamic Therapy

Chemodynamic therapy (CDT) has garnered significant attention in the field of tumor therapy due to its ability to convert overexpressed hydrogen peroxide (H2O2) in tumors into highly toxic hydroxyl radicals (•OH) through metal ion-mediated catalysis. However, the effectiveness of CDT is hindered by low catalyst efficiency, insufficient intra-tumor H2O2 level, and excessive glutathione (GSH). In this study, a pH/GSH dual responsive bimetallic nanocatalytic system (CuFeMOF@GOx@Mem) is developed by modifying red blood cell membranes onto glucose oxidase (GOx)-loaded Fe-Cu bimetallic MOFs, enhancing the efficacy of CDT through a triple-enhanced way by H2O2 self-supply, catalysts self-cycling, and GSH self-elimination. Upon accumulation in tumor tissues facilitated by the red blood cell membrane, the GOx initiates a reaction with glucose to generate H2O2 and gluconic acid in situ. Subsequently, the reduced pH triggers the release of Fe3+ and Cu2+ from CuFeMOF@GOx@Mem, which is immediately turned into Fe2+ and Cu+ by GSH, activating the Fe2+-mediated Fenton reaction. More importantly, Cu+ can also act as an accelerator of Fe3+/Fe2+ conversion, meanwhile, the generated Cu2+ can be further reduced to Cu+ by GSH. Consequently, sustained accumulation of H2O2 and Fe2+ as well as sustained elimination of GSH are achieved simultaneously, providing a unique approach for improving the anti-tumor ability of CDT.

A metal-organic framework functionalized CaO2-based cascade nanoreactor induces synergistic cuproptosis/ferroptosis and Ca2+ overload-mediated mitochondrial damage for enhanced sono-chemodynamic immunotherapy

Cuproptosis is an emerging form of programmed cell death and shows enormous prospect in cancer treatment. Excessive generation of reactive oxygen species (ROS), metal ion accumulation, and the tricarboxylic acid (TCA) cycle collapse are pivotal elements in the triggering of cell death via mitochondrial pathways. Herein, a cascade nanoreactor CaCuZC has been constructed by incorporating nanosonosensitizer IR780 carbon dots (IR780 CD) and calcium peroxide (CaO2) into metal-organic frameworks (MOF) for synergistic cuproptosis-ferroptosis and Ca2+overload mediated immunotherapy. Within tumor cells, CaCuZC dissociates into CaO2, Cu2+and sonosensitizer IR780 CD. The decomposition of CaO2 could generate H2O2 to strengthen the Cu2+-based chemodynamic therapy and Ca2+overload induces amplified intracellular oxidative stress, thus leading to mitochondrial dysfunction. As a result, the combination of Cu2+and Ca2+ overload together induce cascade mitochondrial damage. Moreover, the sonosensitizer IR780 CD generates ROS under ultrasound irradiation to amplify intracellular oxidative stress. In addition, the overloaded Cu2+ released from CaCuZC leads to the aggregation of lipoylated protein dihydrolipoamide S-acetyltransferase, thus resulting in cuproptosis. Furthermore, ferroptosis could been concomitantly induced by CaCuZC with intracellular glutathione (GSH) consumption and lipid peroxidation (LPO) accumulation. The cuproptosis-ferroptosis and Ca2+overload-enhanced synergistic therapy also activates robust immunogenic cell death. CaCuZC enhances the infiltration and activation of tumor-specific cytotoxic T cells to transform a "cold" tumor into a "hot" tumor, activating the anti-tumor immune response. This study provides a cascade of mitochondrial damage strategy for triggering cuproptosis-ferroptosis and Ca2+overload-enhanced immunotherapy and achieving improved therapeutic effects. STATEMENT OF SIGNIFICANCE: To improve the efficacy of tumor immunotherapy, a cascade nanoreactor CaCuZC was successfully constructed based on a self-assembly strategy for cuproptosis-ferroptosis and Ca2+ overload mediated immunotherapy. Upon decomposition within the acidic and GSH-overexpressing tumor microenvironment, CaCuZC released CaO2 and Cu2+ and sonosensitizer IR780 CD. The CaO2 further produced H2O2/O2 and Ca2+ in a weakly acidic environment to strengthen the Cu2+-based CDT and IR780 CD-mediated SDT, respectively. The overload copper ions not only led to cuproptosis, but also efficiently induced ferroptosis. The cuproptosis-ferroptosis and Ca2+overload-enhanced synergistic therapy also activates robust immunogenic cell death. This study presents a cascade of mitochondrial damage strategy for cuproptosis-ferroptosis and Ca2+overload-enhanced immunotherapy.

A covalent organic framework-based nanoreactor for enhanced chemodynamic therapy through cascaded Fenton-like reactions and nitric oxide delivery

Herein, we report a nanoscale composite COF material loaded with copper peroxide (CuO2) and nitric oxide (NO) prodrug via a stepwise post-synthetic modification. The obtained CuO2@COF-SNO can undergo a cascade reaction in the tumor microenvironment to generate reactive oxygen and nitrogen species (ROS/RNS) to enhance chemodynamic therapy of the tumor.

Efficient Cytosolic Delivery of Single-Chain Polymeric Artificial Enzymes for Intracellular Catalysis and Chemo-Dynamic Therapy

Designing artificial enzymes for in vivo catalysis presents a great challenge due to biomacromolecule contamination, poor biodistribution, and insufficient substrate interaction. Herein, we developed single-chain polymeric nanoparticles with Cu/N-heterocyclic carbene active sites (SCNP-Cu) to function as peroxidase mimics for in vivo catalysis and chemo-dynamic therapy (CDT). Compared with the enzyme mimics based on unfolded linear polymer scaffold and multichain cross-linked scaffold, SCNP-Cu exhibits improved tumor accumulation and CDT efficiency both in vitro and in vivo. Protein-like size of the SCNP scaffold promotes passive diffusion, whereas positive surface charge allows its active transcytosis for deep tumor penetration and hence accumulation in the tumor site. The submolecular compartments of the SCNP scaffold effectively protect the active sites from protein bindings, thereby providing a "cleaner" microenvironment for catalysis within a living system. The folded structure of SCNP-Cu facilitates their cytosolic delivery of and free diffusion within cytosol, ensuring efficient contact with endogenous H2O2, in situ generation of toxic hydroxyl radicals (·OH), and effective damage of intracellular targets (i.e., lipids, nucleic acids). This work establishes versatile SCNP-based nanoplatforms for developing artificial enzymes for in vivo catalysis.

A Near-Infrared-II Fluorescent Nanoprobe Offering Real-Time Tracking of Fenton-Like Reaction for Cancer Chemodynamic Theranostics

Chemodynamic therapy (CDT) utilizing Fenton or Fenton-like reactions to generate cytotoxic hydroxyl radicals by metal ions has become a compelling strategy for cancer treatment. Visualizing intratumoral Fenton or Fenton-like reactions especially at a cellular level in real-time can directly monitor the process of CDT, which is not yet feasible. Here, we present a molecule BADA chelating Cu2+ to form Cu-BADA nanoparticles, exhibiting fluorescence quenching properties through intermolecular electron transfer. The nanoparticles are lit up owing to glutathione and acid dual activatable Fenton-like reaction and generation of near-infrared-II fluorescent o-quinones. Moreover, fluorescence vanishing correlated with the decreased intratumoral Cu concentration, thus enabling to track the "on-off" process of Fenton-like reaction specifically in the tumor. Compared to 660 nm-excitation, the o-quinones excited at 830 nm offer deeper tissue near-infrared-II fluorescence imaging with higher resolution. Our results demonstrate a fluorescence nanotheranostic agent for CDT capable of monitoring the spatiotemporal dynamics of Fenton-like reaction.

Copper(II) Oxide Spindle-like Nanomotors Decorated with Calcium Peroxide Nanoshell as a New Nanozyme with Photothermal and Chemodynamic Functions Providing ROS Self-Amplification, Glutathione Depletion, and Cu(I)/Cu(II) Recycling

Uniform, mesoporous copper(II) oxide nanospindles (CuO NSs) were synthesized via a method based on templated hydrothermal oxidation of copper in the presence of monodisperse poly(glycerol dimethacrylate-co-methacrylic acid) nanoparticles (poly(GDMA-co-MAA) NPs). Subsequent decoration of CuO NSs with a CaO2 nanoshell (CuO@CaO2 NSs) yielded a nanozyme capable of Cu(I)/Cu(II) redox cycling. Activation of the Cu(I)/Cu(II) cycle by exogenously generated H2O2 from the CaO2 nanoshell significantly enhanced glutathione (GSH) depletion. CuO@CaO2 NSs exhibited a 2-fold higher GSH depletion rate compared to pristine CuO NSs. The generation of oxygen due to the catalase (CAT)-like decomposition of H2O2 by CuO@CaO2 NSs resulted in a self-propelled diffusion behavior, characteristic of a H2O2 fueled nanomotor. These nanostructures exhibited both peroxidase (POD)-like and CAT-like activities and were capable of self-production of H2O2 in aqueous media via a chemical reaction between the CaO2 nanoshell and water. Usage of the self-supplied H2O2 by the POD-like activity of CuO@CaO2 NSs amplified the generation of toxic hydroxyl (•OH) radicals, enhancing the chemodynamic effect within the tumor microenvironment (TME). The CAT-like activity provided a source of self-supplied O2 via decomposition of H2O2 to alleviate hypoxic conditions in the TME. Under near-infrared laser irradiation, CuO@CaO2 NSs exhibited photothermal conversion properties, with a temperature elevation of 25 °C. The combined GSH depletion and H2O2 generation led to a more effective production of •OH radicals in the cell culture medium. The chemodynamic function was further enhanced by an elevated temperature. To assess the therapeutic potential, CuO@CaO2 NSs loaded with the photosensitizer, chlorine e6 (Ce6), were evaluated against T98G glioblastoma cells. The synergistic combination of photodynamic, photohermal, and chemodynamic modalities using CuO@CaO2@Ce6 NSs resulted in cell death higher than 90% under in vitro conditions.

MnCO3-Au nanoparticles to enable catalytic tumor inhibition with immune activation

Catalytic nanomedicine, activated by endogenous stimuli to enable specific tumor inhibition, has attracted extensive interest in recent years. However, its therapeutic outcomes are often restrained by the weakly acidic microenvironment and limited H2O2 endogenous content. Here, in this study, gold nanoparticles (AuNPs) with glucose oxidase-like activity are incorporated with biodegradable MnCO3 nanoparticles. AuNPs catalyze glucose oxidation to generate gluconic acid and H2O2, while MnCO3 is degraded by the generated gluconic acid as well as the acidic conditions in the tumor region to release Mn2+ and HCO3-. Then H2O2 can be catalyzed by Mn2+ and HCO3- to produce reactive oxygen species (ROS). The effective production of on-site H2O2 leads to promoted intracellular ROS and enhanced tumor inhibition. More importantly, the released Mn2+ ions not only act as a catalytic agent, but also serve as a stimulator of the cGAS-STING pathway to activate anti-tumor immune responses. The in vivo study confirms that MnCO3-Au promotes T cell infiltration in tumors and exhibits a synergistic tumor suppression effect. This study may provide an alternative protocol for combinational tumor therapy utilizing the dual roles of Mn2+ as an emerging catalytic agent as well as an immune agonist.

A convenient colorimetric assay for Cr(VI) detection based on homogeneous Cu(II)-GMP system with oxidoreductase-like activity

Hexavalent chromium (Cr(VI)) is an environmental pollutant and recognized as a human carcinogen. Therefore, it is necessary to develop a simple and sensitive detection technique for Cr(VI). Herein, it is found that Cu2+ interacts with guanosine 5'-monophosphate (GMP) to form a homogeneous Cu(II)-GMP complex (Cu2+·GMP) that efficiently displays the oxidoreductase-like catalytic activity. Cu2+·GMP can catalyze the oxidation between Cr(VI) and substrate 3,3',5,5'- tetramethylbenzidine (TMB), resulting in color change recognized by the naked eyes. Base on this, a convenient colorimetric assay for Cr(VI) detection was developed. The detection limit (3σ/s) of this sensor for Cr(VI) was 23 nM with a linear range of 0.1-25 μM. Moreover, the proposed assay was successfully applied to detect Cr(VI) in different environmental water samples with satisfactory recoveries. Our method is simple, efficient, rapid and cost-effective for Cr(VI) detection without the need for complicated material preparation or special separation, which shows great potential in environmental monitoring.

Application progress of nanomaterials in the treatment of prostate cancer

Prostate cancer is one of the most common malignant tumors in men, which seriously threatens the survival and quality of life of patients. At present, there are serious limitations in the treatment of prostate cancer, such as drug tolerance, drug resistance and easy recurrence. Sonodynamic therapy and chemodynamic therapy are two emerging tumor treatment methods, which activate specific drugs or sonosensitizers through sound waves or chemicals to produce reactive oxygen species and kill tumor cells. Nanomaterials are a kind of nanoscale materials with many excellent physical properties such as high targeting, drug release regulation and therapeutic monitoring. Sonodynamic therapy and chemodynamic therapy combined with the application of nanomaterials can improve the therapeutic effect of prostate cancer, reduce side effects and enhance tumor immune response. This article reviews the application progress of nanomaterials in the treatment of prostate cancer, especially the mechanism, advantages and challenges of nanomaterials in sonodynamic therapy and chemodynamic therapy, which provides new ideas and prospects for research in this field.

A Multisynergistic Strategy for Bone Tumor Treatment: Orchestrating Oxidative Stress and Autophagic Flux Inhibition by Environmental-Response Nanoparticle

Tumor therapy has advanced significantly in recent years, but tumor cells can still evade and survive the treatment through various mechanisms. Notably, tumor cells use autophagy to sustain viability by removing impaired mitochondria and clearing excess reactive oxygen species (ROS). In this study, the aim is to amplify intracellular oxidative stress by inhibiting mitochondrial autophagic flux. Multisynergistic environmental-response nanoparticles (ERNs) are engineered by integrating gold nanoparticles and copper peroxide with borosilicate bioactive glass. The controlled release of copper and inhibition of autophagy flux triggered an overabundance and accumulation of oxidative stress within the tumor cells. This stress triggered immunogenic tumor cell death, believed to initiate a systemic immune response. The tumor microenvironment (TME) transitioned back to a normal physiological state as tumor cells are ablated. ERNs responded to the microenvironment changes by depositing hydroxyapatite on the surface and spontaneously enhancing bone regeneration. This innovative formulation facilitates the functional transition of ERNs from "anti-tumor therapy" to "biomineralization" that kills cancers and induces new bone formation. Overall, it is shown that the ERNs effectively eradicate cancers by utilizing chemodynamic therapy, starvation therapy, and immunotherapy.

Catalytic Biomaterials-Activated In Situ Chemical Reactions: Strategic Modulation and Enhanced Disease Treatment

Chemical reactions underpin biological processes, and imbalances in critical biochemical pathways within organisms can lead to the onset of severe diseases. Within this context, the emerging field of "Nanocatalytic Medicine" leverages nanomaterials as catalysts to modulate fundamental chemical reactions specific to the microenvironments of diseases. This approach is designed to facilitate the targeted synthesis and localized accumulation of therapeutic agents, thus enhancing treatment efficacy and precision while simultaneously reducing systemic side effects. The effectiveness of these nanocatalytic strategies critically hinges on a profound understanding of chemical kinetics and the intricate interplay of reactions within particular pathological microenvironments to ensure targeted and effective catalytic actions. This review methodically explores in situ catalytic reactions and their associated biomaterials, emphasizing regulatory strategies that control therapeutic responses. Furthermore, the discussion encapsulates the crucial elements-reactants, catalysts, and reaction conditions/environments-necessary for optimizing the thermodynamics and kinetics of these reactions, while rigorously addressing both the biochemical and biophysical dimensions of the disease microenvironments to enhance therapeutic outcomes. It seeks to clarify the mechanisms underpinning catalytic biomaterials and evaluate their potential to revolutionize treatment strategies across various pathological conditions.